Browsing by Author "Stepniewski, Adam S."

To clinically verify the bony response to a press-fit acetabular component, this study assessed 5 postmortem-retrieved pelves with unilateral total hip arthroplasties. Changes in periacetabular bone density between implanted and contralateral bone were assessed with dual energy x-ray absorptiometry and computed tomography. At a mean of 9.1 years postarthroplasty, bone density decreased an average of 1.5% to 7.1% proximal and 12.8% medial to the cup. This supports shorter-term in vivo investigations demonstrating periacetabular stress shielding proximal to press-fit cups as well as computer models predicting bone loss medially, but in much greater magnitudes. Unlike femoral remodeling, the average magnitudes of pelvic bone loss are not extensive; therefore, we question whether periacetabular remodeling should be a primary concern for orthopedic surgeons.

Perineurioma is a rare benign peripheral nerve sheath tumor featuring perineurial differentiation. Perineurioma occurs sporadically with only one reported case in the setting of neurofibromatosis type 1 (NF-1). We present a 6.7-cm soft tissue perineurioma of the lower leg in a 51-year-old man with proven NF-1. The tumor displayed whorled and fascicular pattern with infiltrative margins and expressed EMA, GLUT-1, claudin-1, and CD34. Electron microscopy confirmed diagnosis. Furthermore, lipomatosis, cutaneous angiomatous nodules, vasculopathy, and iliac spine lesion consistent with non-ossifying fibroma were observed. Tumor DNA revealed no NF2 mutations or chromosomal aberrations but a germline NF1-deletion (c.449_502delTGTT) was detected in his blood sample. His brother displayed neurofibromas, duodenal ganglioneuroma and colonic juvenile polyp, and his mother a neurofibroma, cutaneous squamous cell carcinoma, and jejunal gastrointestinal stromal tumor (GIST); both were affected by NF-1. In conclusion, perineurioma may rarely be NF-1 related and should be included in the spectrum of neoplasms occurring in this disorder.

Background The first description of local fascio-cutaneous flaps used for the coverage of soft tissue defects of the limbs originates from the 1980s. Over the years, this technique has advanced, and in the meantime, a sub-group of flaps named perforator-based propeller flaps has gained increased attention. In our study, we aimed to demonstrate our experience of operating surgeries with perforator-based propeller flaps and to compare this technique with other flap techniques, which are to reconstruct tissue defects of the knee, lower leg, and foot. Methods A systematic retrospective search for flap procedures for defect reconstructions in the knee, lower leg, and foot from our database was performed. All data between January 2010 and August 2018 were considered. We identified 56 procedures performed on 14 female and 42 male patients with the mean age of 54.13 years. Reconstruction procedures consisted of 34 free flaps, 14 perforator-based propeller flaps, and eight other perforator-based flaps. Compared to free flaps, the perforator-based propeller flaps had shorter surgery duration by 46.6% (p < 0.0001) and the complication rate in the cases of perforator-based propeller flaps was reduced by 31.14% (p = 0.0315). Furthermore, the operations carried out with perforator-based propeller flaps resulted in a significantly lower rate of revisions by 36.03% (p = 0.0204), compared to those with free flaps. The majority of the donor sites of free flaps were self-closing with the direct suture (p = 0.004). Conclusions Based on our findings, we can propose the applicability of perforator-based flaps in treating defects of the knee, lower leg, and foot. With a correct indication, perforator-based propeller flap represents a promising alternative to free flaps, with its significantly shorter surgery duration, lower complications rate, and lower revision rate. However, both techniques of the free flap transfer and the transfer of local pedicle-based flap possess their advantages and disadvantages. Therefore, it is hard to define which microsurgical technique is exclusive in treating lower leg defects.